HUBS1403 - Week 10 Flashcards
(17 cards)
What is an electrical synapse?
Direct cell-to-cell communication via gap junctions.
Allows fast, bidirectional signal transfer and synchronizes activity in neurons.
What is a chemical synapse?
Unidirectional signal transmission from presynaptic to postsynaptic neuron using neurotransmitters.
Most common type in the human nervous system.
What is the first step in transmitting an action potential at a chemical synapse?
AP arrives at synaptic terminal.
This initiates the process of neurotransmitter release.
What happens after depolarization at a chemical synapse?
Opens voltage-gated Ca²⁺ channels.
This allows calcium ions to flow into the neuron.
What triggers vesicle fusion with the membrane in a chemical synapse?
Ca²⁺ influx.
This is essential for the release of neurotransmitters.
What occurs after neurotransmitter is released into the synaptic cleft?
Neurotransmitter binds to receptors on the postsynaptic membrane.
This initiates the postsynaptic electrical response.
What changes occur in the postsynaptic membrane due to receptor activation?
Changes ion channel permeability.
This leads to an electrical response in the postsynaptic neuron.
How is the neurotransmitter signal terminated?
Degraded, diffused, or reuptaken.
This ensures that the signal does not persist indefinitely.
What is an EPSP?
Excitatory Post-Synaptic Potential.
It depolarizes the membrane and increases the chance of an action potential.
What is an IPSP?
Inhibitory Post-Synaptic Potential.
It hyperpolarizes the membrane and decreases the chance of an action potential.
What determines if an action potential is triggered in the postsynaptic neuron?
Summation of EPSPs and IPSPs at the axon hillock.
This integration of signals is critical for neuronal firing.
What is synaptic plasticity?
Synapses change strength with use.
This is a fundamental mechanism for learning and memory.
What does Hebb’s Law state?
Neurons that fire together wire together.
This principle underlies the concept of synaptic strengthening.
What is LTP?
Long-Term Potentiation.
It involves increased AMPA receptors and sensitivity, leading to stronger EPSPs.
How does neuroplasticity aid recovery after brain injury?
Brain reorganizes connections and recruits new pathways.
This allows unaffected regions to compensate for damaged areas.
What role does adult neurogenesis play in recovery?
Aids recovery through the generation of new neurons and synaptic remodeling.
Particularly significant in areas like the hippocampus.
What is the time-limited plasticity window after brain injury?
The period during which functional recovery is greatest.
This is crucial for maximizing rehabilitation outcomes.
